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<html lang="en">

<head>
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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<style>
    div {
        width: 400px;
        height: 400px;
        background-image: url(./../resources/素材3.png);
    }
</style>

<body>
    <div>div标签</div>
</body>

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